Clinometer device



March 1, 1938, i A. G. H. STRAATMAN CLINOMETER DEVI CE FiledJan. 23, 1936 f/af.

M/IFSTOCK 2 Illlll/fllll g 7 Patented Mar. t, ltddd Netherlands, assigncr to Shelli llteve l lopment Company, San Francisco, (Calliifi, a comrahon oi welaware Application llannary 23, with, Serial No. iitltdtt lin the Netherlands February l, 129% (Claims. (as ass-i) This invention pertains to an apparatus for the orientation of various devices located in boreholes deviating from .the vertical, and is a fur-' ther improvement in the process and apparatus disclosed and claimed in my prior Patent No.

hit

1,806,509, directed to the orientation oi whipstocks by means of a clinometer comprising an acid bottle.

In determining the position of various bodies located in bore-holes, such as whipstocks, straightening wedges, core-barrels, cores, etc., the orientation does not necessarily have to be effected with regard to the points of the compass. Very often it is only important to ascertain the position of the deviation plane of the bore-hole, that is, of the vertical plane passing through the axis of the deviating bore-hole, with regard, for example, to the symmetry plane of a whipstock, or to a plane passing through a definite mark on a core or a core barrel. In the case of whipstocks, any desired directional change in drilling may thereupon be eflected by a suitable adjustment in the angle between the deviation plane of the bore-hole and the symmetry plane of the whipstock. Similarly, in orienting cores or core barrels, once the position of the core with regard to the deviation plane of the bore-hole is recorded, and the azimuth and the amount of dip of the bore-hole is determined by an additional measurement .according to well-known methods, a complete orientation of the core may he eflected on withdrawing it from the well.

It is the object of this invention to provide an apparatus for positively orienting bodies located in bore-holes with regard to the deviation plane of the latter by means of a clinometer of simple and rugged construction, dispensing with the use of acid bottles and similar relatively fragile devices, and 1 allowing the desired determinations to be effected in a fraction of the time usually consumed for such operations.

The construction and method of operation of the present clinometer will be understood from the following description of a preferred embodiment thereof, to which, however, this invention is in no way limited, since it consists broadly in impressing two marks on a suitable deformable material contained within the clinometer. one of said marks denoting the deviation plane oi the well, and the other the actual position in a horizontal plane of the body whose or entation is to be eilfected. The first of these marks is impressed by means of a solid indicator free to move within the clinometer under the action of the force of gravity, such as a free rolling ball, a

pendulum, etc., while the second mark is impressed by means of'a marker connected in fixed hnown relationship to the body to be oriented.

In the drawing: Fig. 1' is a cross-sectional elevation view of the clinometer lowered into the well,

Fig. 2 tea plan view of the'top face of bolt 25 of Fig. l; and i Fig. d-is a diagrammatic cross-sectional view showing a whipstock provided with. marking means attached to the end of a tubing string, and a clinometer being lowered into operative position, according to the present invention.

Referring to Fig. 1, an extension i is rigidly connected to the body, such as a. whipstockor a core barrel, whose position with regard to the deviation plane of the bore-hole is to be determined. Although extension II is shown of tub ular shape on the drawing, it may be given in practice any other suitable form. A marking -means, such as a bolt it is carried at the lower end oi extension i and has its upper face matched with an arrow or other mark in relief in a certain known position with regard to the extension i, and therefore, to the body to be oriented.

The clinometer consists of a casing 2 provided with acentral bore having a relatively smaller diameter in its upper part, as shown at t and a relatively larger diameter ,in its lower part, as shown at it and it. A sleeve it provided with an annular shoulder 22 is amxed within the easing bore it and is adapted to slide over the bolt it, when the casing is moved downward. The upper part of sleeve N forms a cylinder liner It for the bore it, holding amovable member such as piston i'l. Deformable means, such as rings ltand it,- made of lead or other suitable plastic material, aresecured to the piston by means of piston rod it and screw i9. Above the ring it, an annular shoulder M5 on the piston rod may form a circular guiding face or groove l3 partly supporting a ball M and protecting ring l5 from premature deformation. The ball It is also partly supported by the inner wall of the cylinder liner it, \n such a way that it is free to roll around the piston rod it under the action of gravity. The annular shoulder to is of smaller diameter than the ring l5. Above the cylinder liner It, the bore i2 is 'widened at H to a radius slightly exceeding that of the annular shoulder it plus the diameter of the ball l4, and slighty smaller than the outer radiu: of ring l5 plus .theidiameter of the ball M.

The upper part of the piston rod extends into contains a spring 5 forcingthe piston rod and the piston down. This bore is closed at the top by means of a screw 3. The upper end of the piston rod is equipped with a sealing plug 6 and a ball valve 9 opening downwards against the action of a spring 5-A, which permits the displacement of the liquid filling the space above the piston to the space below the piston during its upward stroke in the following manner: the liquid filling the space H passes by means of a groove 1 in the piston rod I0 to the space above sealing plug 6, thence through passage 8 past the valve 9, which is opened against the action of spring 5-A, and through passage 8-A to the space below the piston. The channel 8 has a small diameter which allows only a slow displacement of the liquid and a slow motion of.

the cylinder.

The clinometer 2 is provided at the top with screw threads or other attachment means by which it may be connected to guide members or rods serving to lower the instrument into the bore-hole and to apply, if desired, a necessary downward pressure.

The clinometer is operated as follows:

The body, for example, a whipstock, whose position with regard to the' deviation plane of the bore-hole is to be determined, is lowered into the bore-hole by means of a string of tubing or rods, which may subsequently be withdrawn from the well or may remain therein. The extension I, which is rigidly connected to the whipstock, is preferably placed as a connecting part between said tubing and the whipstock, the arrow on the bolt 26 denoting a certain known plane, for example, the symmetry plane of the whipstock.

The cylinder space in the clinometer 2 above the piston is filled with-oil or any other suitable liquid, and the clinometer is run into ,the borehole, preferably through the tubing by means of which the whipstock had been lowered.

When the lower face of the ring 20 comes in contact with the end of the bolt 26, the weight of the clinometer and of the string of tubing or rods to which it is connected will cause an impression of the ends of the arrow in the soft material of the ring.

The clinometer 2 will then tend to move further down, this movement being impeded by the liquid contained in the cylinder above the piston, which liquid can escape only very slowly through the vertical groove 7, valve 9 and channel 8. Due to the deviation of the bore-hole from the vertical; the ball I will move to its lowest position on groove l3, being assisted in this by the sliding movement of the cylinder liner past the ball. This lowest position of the ball will obviously lie in the deviation plane of the well.

When the piston I1 is about to reach the end of its upward stroke, the ball [4 reaches the level of the widened portion ll of the cylinder chamber, falls out of the groove I3, and is supported by the upper face of ring l5 and the cylinder wallll. On the piston moving further upwards, the ball is caught between the head of the cylinder chamber and the upper face of the ring IS, the pressure exerted being sufiicient to make an impression in the soft material of the ring IS.

The clinometer may then be withdrawn from the well and taken apart, the position of the extension l, and therefore of the whipstock, with regard to the deviation plane of the bore-hole being easily determined from the two impressions made respectively on rings 20 and IS, the position of these rings relative to each other being known. v

Although the present invention is especially useful for setting whipstocks in directional drilling, it is evident that the position of any other body located in a bore-hole, such as a-core or a core-barrel, may be determined in the same manner with regard to the deviation plane of the bore-hole.

It is also understood that'hydraulic pressure applied, for example, by pumping a. column of drilling fluid down the tubular string I on top of the clinometer casing 2 may be used instead of positive mechanical pressure to cause the relative movement between the piston and the body of the clinometer.

. I claim as my invention:

1. A device for determining the position of a body in an inclined borehole with regard to the deviation plane of the borehole, said body carrying a marking means indicating its position in the horizontal plane, said device comprising a casing adapted to be lowered into the borehole, a solid indicator means within the casing tending to shift its position under the eifect of gravity, and axially movable deformable means within the casing adapted to be forced into contact with said solid indicator means by pressure against the body in the borehole, whereby an impression of said solid indicator means within the casing and of the marking means is impressed on the opposite sides of said deformable means.

2. A device for determining the position of a body in an inclined bore-hole with regard to the deviation plane of said bore-hole, comprising a casing adapted to be lowered into the bore-hole, v

a cylinder in the lower part of the casing, a piston movable in' said cylinder, a gravity-responsive solid indicator means above the piston, adapted to remain in the deviation plane of the bore-hole within the cylinder, marking means body in an inclined bore-hole with regard to the deviation plane of said bore-hole, said device comprising a casing adapted to be lowered into the bore-hole, a cylinder in the lower part of the casing, a piston movable in said cylinder, a free-rolling ball above the piston within the cyllnder adapted to seek by gravity the deviation plane of the borehole, marking means connected in rigid relationshipto the body in the bore-hole and adapted to displace the piston when the casing is pressed against said body, and deformable means on the opposite sides of the piston adapted to receive a mark from said last named marking means and a mark from said ball in the cylinder when the piston is displaced within the cylinder.

4. In the apparatus of claim 3, an oil filled cylinder chamber'for the piston, and valve means permitting a slow displacement of the oil from said chamber when the piston moves through its stroke. I

5. A device for determining the position of a body in an inclined borehole with regard to the deviation plane of the borehole, said body carrying a marking means indicating its position in a horizontal plane, said device comprising a casing adapted to be lowered into the borehole, an opening in the bottom of said casing for receiving said marking means, a movable transverse member within said casing, a solid indicator means above the member tending to shift its position within the casing under the effect of gravity, a first deformable means carried on the upper face of the movable member out of contact with said indicator means, and a second de- 10 formable means carried on the lower face of said movable member, said first and second deformable means being adapted to receive an impression from said solid indicator means within the casing and said marking means-on the body in the borehole, respectively, when said movable member is moved into contact with said solid indicator means by pressure against the body in the borehole.

ALPHONS GERARD HUBERT STRAATMAN. 10 

